Yes, the home button assembly is of a completely different design on the 4th Gen iPad.

But, for most of us, the home button assembly is transferred from the original device so that wouldn't be an issue.

Suppliers here in the UK are charging 25% more for a 4th Gen digitiser that is identical in every way (no home button included). Not sure if that's because they're paying more for it and don't know it's identical or if they're ramping the price because customers won't realise.

We are a large repair shop and we fit iPad digitizers on a daily basis. The iPad 3 Digitizer will indeed fit the iPad 4, we only ever use the iPad 3 digitizers for both iPad versions, the cables do fit, we have changed in excess of 300 iPad 3 digitizers into the iPad 4, you just have to position them carefully and correctly, If you don't know what you are doing then i suggest you hire someone that does, and do not state they don't fit, as they clearly do, search Google you will be amazed how many people fit iPad 3 into iPad 4 as the iPad 3 are slightly cheaper, you will need to transfer the home flex over as these are different, the front camera are also the same on both versions.

Hi. I am repairing my first ipad 4 digitiser this morning. I thought I would test an ipad 3 digitiser originally bought in error for an ipad 2. It's an EL digitiser purchased off eBay. I can confirm it is fully Woking on the 4 at this stage. Hope this helps.

You will have to take the home button out of the old glass and put it on the new glass (just like all the ipads) but otherwise, functionality and fitment are the same. Vendors just say it's different so that they can charge $10-15 more.

Just like to add an update to the post I wrote yesterday so today after a few minutes fighting to get the flex to sit rightish as the flex is clearly a different lenth and width to the ipad 4 digitizer ..

Got screen fitted and now there is dead spot on screen not that worried as this was a test just to see could it be done and my opinion is don't bother just buy the correct part for the ipad generation you need it will save you time and heartache

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